混凝土棱柱体试件抗压强度尺寸效应探讨  

Study on Size Effect on Compressive Strength of Concrete Prism Specimen

作　　者：唐腾飞 黄耀英[2] 练迪 陈义涛[2] 徐佰林 

机构地区：[1]中国电建集团贵阳勘测设计研究院有限公司,贵州贵阳550081 [2]三峡大学水利与环境学院,湖北宜昌443002

出　　处：《人民黄河》2017年第12期142-145,共4页Yellow River

基　　金：国家自然科学基金资助项目(51209124)

摘　　要：现行《水工混凝土试验规程》(DL/T 5150—2001)并未对高应力比条件下混凝土徐变试验棱柱体试件的抗压强度尺寸效应作出明确规定,因此从定性和定量的角度探讨棱柱体试件的尺寸效应问题。通过对15个同截面、不同高度的混凝土棱柱体试件进行抗压强度试验,较系统研究了试件纵向高度与横向长度比值和抗压强度的关系,得到棱柱体试件抗压强度尺寸效应的临界尺寸。收集大量临界尺寸范围内混凝土棱柱体试件抗压强度试验资料,建立了混凝土尺寸效应广义回归隐式神经网络模型,计算分析结果表明:规范中抗压强度折算系数无法满足高应力比下徐变试验荷载加载要求,可利用本文建立的隐式神经网络模型预测不同尺寸的混凝土试件的抗压强度比值进行高应力比下的徐变试验。In view of the existing concrete test specification,the size effect on compressive strength ratio of the prism concrete specimen in the creep experiment under high stress has not been explained. Therefore,this article did further research from the perspective of qualitative and quantitative to prism specimen 5 s size effect is sue, first of all, 15 group prism specimens with same cross section and different heights of the compressive strength experiment, systematically studied the relationship between vertical height of the specimens and the compressive strength,got the critical size of compressive strength size effect of prism specimens; Then collected a large number of critical dimension with-in the scope of prism compressive strength experiment data and the generalized regression implicit network model of size effect of concrete was established. The calculation and analysis results show that the compressive strength reduction factor specified in the specifications can’ t meet the requirements of the creep test under high stress,in this paper,building an implicit network model to predict different size of concrete compressive strength ratio of the specimens in the creep experiment under high stress can be used.

关 键 词：尺寸效应 临界尺寸 隐式神经网络模型 高应力比 徐变试验 

分 类 号：TV431[水利工程—水工结构工程]